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An anonymous reader recommends a project carried out recently by Serge Brunier and Frédéric Tapissier. Brunier traveled to the top of a volcano in the Canary Islands and to the Chilean desert to capture 1,200 images — each one a 6-minute exposure — of the night sky. The photos were taken between August 2008 and February 2009 and required more than 30 full nights under the stars. Tapissier then processed the images together into a single zoomable, 800-megapixel, 360-degree image of the sky in which the Earth is embedded. "It is the sky that everyone can relate to that I wanted to show — it's constellations... whose names have nourished all childhoods, it's myths and stories of gods, titans, and heroes shared by all civilisations since Homo became sapiens. The image was therefore made as man sees it, with a regular digital camera." The image is the first of three portraits produced by the European Southern Observatory's GigaGalaxy Zoom project.

It's just barely getting by! It looks like if he were to provide the full res version as a downloadable, it would be 4.42GB large. It would have been nice if there were say a wallpaper-sized version instead of that dinky thumbnail though.

It would appear that the Coral servers are acquiring bits and pieces as they are able. When I reloaded the link, I was able to see much more of the site than at first. Be patient... and try reloading in a few minutes.

It should be standard procedure when posting any article to Slashdot, to run it though Coral *FIRST*, so their servers can load and mirror everything. Then post the Coral link.

In general I agree with you. However, in this case it wouldn't help out a ton. Coral would get the page and the fully zoomed out image, which would at least be something, but is not the purpose of this post...there are countless wide angle photos of the sky you can find all over the internet. It wouldn't cache any of the zoomed data unless someone manually went through and zoomed in on everything.

I did try to zoom in on a few things, in an effort to get SOMETHING into the Coral pipeline. About an hour later, there were some areas of the sky map that were zoomable all the way. Hey, a little success is better than none.

The real solution would have been for the person submitting the article to have used Coral *first*, to get the whole thing mirrored, THEN submit the article with the Coral link.

I've only submitted a handful of articles, none of which got published... but I used Coral before submitting t

When I saw the article, it was only about a MINUTE old, and had ZERO comments. No, I did NOT expect it to have *already* been Slashdotted. I'm glad I was quick enough to at least get the Coral servers to grab SOMETHING as the deluge began, so people could at least see a *portion* of the site before it's servers smoldered.

Oh, I dunno; I'm not too impressed by the way that the stars near galactic north and south are spread out into lines. This image doesn't use the best sort of sphere-to-plane projection. I wonder if we can get it in a better projection? I'm not sure I even want to see what looks like if I try to zoom in on the polar regions.

Does anyone know what kind of method they use to "stitch" together the images? What kind of projection they use, so the final imagen does indeed look like the milky way, and not stretched nor distorted?

Go wide. And you'll have to go much faster than you think. Play around, but IIRC with no tracking you can only reasonably get about 20 seconds out of a 50 mm (35 mm camera) lens. Faster film gets you a deeper image but more grain of course. Most constellations fit nicely in the frame from a 50 mm lens.

Unfortunately, you won't get anything like this with film, at least not without an incredible amount of work and some really excellent tracking. Film rules for long exposures but digital is unbeatable for

1) It's been years since I did any work with film, so I'm afraid I can't help you there. I've just got a DSLR that I use now.
2) ~20 seconds. If you go very far beyond that, you'll end up with trails instead of nice clear shots. 30 seconds is passable, you'll just end up with tiny, tiny trails - probably not that noticeable unless you look closely. You may be able to stretch that out a bit more if you have near-superhuman vision, a geared tripod, and a steady hand, but I wouldn't count on it. That's

Also, I hate to double post, but make sure you lock up the mirror on your camera if you have that option. Mirror slap is never good. I just picked up a nice Manfrotto tripod/head, but I still think it takes a few seconds for any vibrations to completely settle. Locking your mirror up should take care of that. It's a minor detail, but one worth mentioning.

After reading your message and the one about the relative strengths of film and digital, it occurred to me to wonder what you could do with digital tracking. Basically stitching together a LOT of shorter exposure digital shots and correcting for the motion of the earth algorithmically to synthesize a long exposure image. It seems like an obvious hack for someone with a digital back and a fixed scope.

In my experience, it didn't do much to make it look like a longer exposure. That may be because of the light pollution where I was, or the relatively small number of exposures I was toying with. It does, however, clean up some of the noise in the pictures. Not really an issue when you're only using ~20 second exposures, especially if you use a dark frame [wikipedia.org] and a bias frame [wikipedia.org]. For longer exposures, though, the noise starts adding up, and multiple exposures

> 1) Film type. What should I go with? I was thinking of a low-grain slow film like Reala, but would a faster film be preferable?
> 2) Shutter length. What is the minimum shutter length to get a deep view of the sky but also avoid capturing the rotation of the earth?
> 3) Lens. Is there an ideal focal length? I was thinking wider is better to capture more of the sky and possibly some earth-based objects

It is easy to estimate this. The sky (well...the Earth) rotates in about 24 hours: given the

Towards the end of the web page they say that they stitched all the images together using this software [autopano.net].
I personally use this free program [cs.ubc.ca] for photo stitching, but if you look around with google, you can find plenty of them to use.

800 megapixels would be a very large resolution for a normal image of a simple subject like, say, a person. But when you consider that this image is covering 360 degrees of night sky, which changes nightly (constellations and planets rise and set just like the sun), the resolution is not so great. An exposure time of 6 minutes (during which everything is moving) goes to show how "blurry" even an 800 megapixel image of the night sky (an enormous subject) must be. This doesn't take anything away by the beauty of this project, but I think it's important to put sensational measurements such as "800 megapixels" in context.

The motored tracking tripod/device is really needed for star shooting (what is actually easy to manufacture itself) because over 2 second exposure makes stars leaves trails.

For normal moon shooting even tribod is not needed, becase when moon is clear, it is like shooting on earth a subject on sunlight. 1/250 with F8 ISO 100 (So you can easily shoot by hand using 300mm focal lenght). Stars can be captured too with 4-8 seconds exposure, but you end up having trails on them and moon overexposured totally only

additional: stupid resolution photos of the globe are misleading in that for a 21,000x21,000-pixel image, each pixel represents over a mile on the ground. So, it ain't that impressive. Come back to me when someone montages captures taken on Google Earth taken vertically downwards at a mean altitude of 6 miles ASL-should take pixel resolution to 6 feet or less, meaning over an 800-fold increase in pixel resolution. 16.8 million pixels of a side will do just nicely. THEN I'll be impressed.

Well I can tell you it certainly doesn't end well on the windows side either if you choose to click "Set as Desktop Background" instead of the "Open With" option that lives right below. It ate right through all my glorious 8 gigs of memory and pegged my i7 for a good minute before I could kill explorer. I would not recommend it in the future...

. This doesn't take anything away by the beauty of this project, but I think it's important to put sensational measurements such as "800 megapixels" in context.

If you want to put these measurements in context, you consider what is currently occurring in astrophotography, not the extreme resolution that can be achieved by photographing smaller subjects. The resolution is virtually irrelevent, the time taken and the measures with which to achieve it are far more crucial to this.

As you quite clearly have no knowledge of such a subject (referencing you point regarding moving, which is a trivial aspect for any astrophotographer using a tracking mount / autoguider,

As the article and the 800 megapixel resolution referenced in the headline are targeted at a general audience, not astrophotography experts, and as I have a solid math/physics background, I'm in a perfectly comfortable position to help put a photograph's resolution in context. Most people who read the headline are not going to think of the resolution given in an astrophotographical context, but in comparison to the resolutions of the digital cameras they are personally familiar with.

Yeah, I think I was a little aggressive, there, so my apologies, but I do stick with what I'm saying, even for the layman, blaming resolution for clarity is not particularly accurate. That being said, one would only cite resolution for the layman.

The surface area of a sphere, is 4pi r*2, so those 800M pixels,
match the surface of sphere 8000 pixels in radius, or 50132
pixels in circumference. So each pixel represents a square on
the night sky about 26 seconds of arc in each direction. That isn't
really very accurate, most objects in the sky are lot smaller than
that. It might just have enough resolution to show some structure
in the andromeda galaxy which is (178 by 63) arc min in size.

For the night sky, 800 megapixels is impressive. But for earth, its not particularly big. go to gigapan.org and you'll find thousands of gigapixel images, including ones taken at night, requireing long exposures (even if nothing near 6 mins)

Unfortunately, many hosting companies make bold claims about their capabilities without actually being able to deliver on those promises. In this case, the host appears to be ovh.com [ovh.com] (judging by whois info on the IP), providing a dedicated server. Of course, this does leave open the possibility that the server is badly configured for traffic on this scale.

The server's still working. I doubt they expected the full force of slashdot. And this isn't like a normal posting, this is the sort of thing everyone will want to see for themselves.. And it can't help that it's a huge image.

You can't actually see the 800-megapixel image. You have to contact the photographer to get the full-resolution image

They have a couple of decent sized static images, some desktop sizes, and one that dynamically loads when you zoom in, ala google maps. I don't know if the last one goes to the full 800MP when you zoom.

That picture looked pretty impressive on display "in the Atrium of the Monte-Carlo Casino, Monaco." Unfortunately, it's no longer on display. It's an interesting story but I can't believe they paid someone to do this (if he did get paid which I assume he did).

Funny thing is, that's not the picture. The photographer, Brunier, decided to lower every copy he released electronically to either 18MP max, or be that one zoomable version. The 800MP version is only available through him, only for professionals, and he holds the copyright.

What the dick pretty much did, was give the astronomical community something to clap about and use to get more of an audience, while getting his own name on it. He didn't do anything serious with this, like let other people have it, or u

Yeah what a jackass. He spends 30 entire nights over 6 months doing photography (something that he appears to do as part of his profession) and then expects to maintain a little bit of creative control over his work? Pffft!

Sarcasm aside, grow up a bit. He's made the zoomable version available, and even aside from that 18MP is pretty darn good. It's a good quality image you are working with, and you could do quite a bit with it. I've made 40" long prints from 6.7MP images and they end up looking very good. Y

So I take it that if you work 30 days at your job, you're more than happy to let anyone take as much of your paycheck as he/she pleases?

If a person does work, they are entitled to decide what to do with the proceeds of that work, no matter whether it be keep it private, release it to the public, or (as this guy has done) choose something somewhere in between.

You can't get it anywhere except the artist. I set him an email, and he sent a very prompt reply that it's for profesional use only, without actually knowing wether or not I was a professional.

I'm guessing that even though this project, GigaGalaxy Zoom, is done by the ESO, a intergovernmental organization, the image is just under license from the "artist" (in this case, "man with too much time for tedium"), so don't hold your breath about finding it anyway.

All of them came AFTER I was responded to, except for the one response to the article, Mr. Coward. You don't know who I am, where I'm from, or what I do, or anything else about me, which negates the "me not being a professional" argument. And, if I were really just trolling, you wouldn't have to post anonymous, now would you?

Most people who live in cities never get to see even a fraction of the night sky. Even thougb I live in rural Colorado where we can see the Milky Way fairly regularly, I want to thank you so much for sharing with everyone what we are missing out on, night after night. This is way better than TV.Cheers.

I was recently at Yosemite during the Perseid meteor shower, and I got to really look at the Milky Way "scar" for the first time with my own eyes. My parents have a house in rural Texas, but the visibility was nowhere near what it was smack dab in the middle of a wide open Yosemite field at midnight.

I spent a couple years in Antarctica [gdargaud.net]: clearest sky in the world by very far (see recent/. article about ridge A [slashdot.org]). When I was at Dome C [gdargaud.net], we would go lay down in the snow and watch the stars, never mind the sub -70C temperatures. The stars didn't twinkle at all (no turbulence) and appeared painted on a black ceiling. The main problem was getting back inside before you were frozen solid to the ground.

I had my own telescope, but my pitiful attempts at seeing anything were thwarted by the vexatious cold and my own incompetence at astronomy [gdargaud.net].

Splendid. For those of us who 'know nothing', it would be useful to have some orientation. Where is the so-called Pole Star or Southern Cross? Big Dipper/Plough? And which is the spot of the Hubble deep field?

Most people who live in cities never get to see even a fraction of the night sky. Even thougb I live in rural Colorado where we can see the Milky Way fairly regularly, I want to thank you so much for sharing with everyone what we are missing out on, night after night. This is way better than TV.
Cheers.

Those of us temporarily taking up abode in the Iraqi desert also don't get to see much of the stars. The sand/dust that is always in the air is worse than looking at the stars just a mile from downtown Seattle! The dust in Iraq is far worse than any light pollution I've ever encountered while living in Seattle.

My RSS reader shows changes in feeds. The original RSS summary for this article had "its" without the apostrophe -- correctly, as anyone with half a brain knows. The latest RSS feed, and the actual story page, show "it's". Hint: if you can't replace "it's" with "it is" in the sentence, it's (yes, really) wrong.

If you really want to be pedantic about it, "it has got" is not proper grammar either, and no one would ever say "it's one little problem" in place of "it has one little problem", so you still fail. Nice try, though.

Sites are claiming copyright as a concern, so you need to contact the artist to get the pic. I know downloading it is almost impossible due to the size, but really, pictures of the stars? Isn't this just tedious work that wouldn't be covered by copyright?

If you don't like the copyright then there is nothing stopping you going out for 30 nights and taking 1,200 6-minute exposures.
Tedious maybe, but not easy.
Be thankful for copyright. Without it they may never have shared this picture with us.

That is really amazing. It's one of the best images of the sky I've ever seen that wasn't taken by the Hubble. The only thing that would make it better is if they made it interactive and labelled the stars and constellations. Very cool.